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The relationship between structural properties and functional characteristics of starch remains a hot subject among researchers. The crystalline property is a substantial characteristic of starch granules, undergoing different changes during modification techniques. These changes are closely related to the functional properties of modified starches. Physical modifications are eco-friendly techniques and are widely adopted for starch modifications. Therefore, understanding the impact of changes in crystalline properties during different physical modifications on starch functionality is the ultimate way to improve their industrial utilization. However, the existing literature still lacks the elucidation of changes in functional properties of starch in accordance with its crystalline properties during different physical treatments. Hence, this review summarizes the effects of the most important and widely used physical modifications on starch crystalline properties, highlighting the alterations in various functional properties such as hydration, pasting, gelatinization, and in vitro digestibility resulting from changes in crystalline characteristics in a single comprehensive discussion. Furthermore, the current review gives direction for envisaging the functionalization of starches based on deviations in the crystalline properties during several physical treatments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, corn starch was used as the raw material, and modified starch was prepared using a method combining plasma-activated water and ultrasound treatment (PUL). This method was compared with treatments using plasma-activated water (PAW) and ultrasound (UL) alone. The structure, thermal, physicochemical, pasting, and functional properties of the native and treated starches were evaluated. The results indicated that PAW and UL treatments did not alter the shape of the starch granules but caused some surface damage. The PUL treatment increased the starch gelatinization temperature and enthalpy (from 11.22 J/g to 13.13 J/g), as well as its relative crystallinity (increased by 0.51 %), gel hardness (increased by 16.19 %) compared to untreated starch, without inducing a crystalline transition. The PUL treatment resulted in a whitening of the samples. The dual treatment enhanced the thermal stability of the starch paste, which can be attributed to the synergistic effect between PAW and ultrasound (PAW can modify the starch structure at a molecular level, while ultrasound can further disrupt the granule weak crystalline structures, leading to improved thermal properties). Furthermore, FTIR results suggested significant changes in the functional groups related to the water-binding capacity of starch, and the order of the double-helical structure was disrupted. The findings of this study suggest that PUL treatment is a promising new green modification technique for improving the starch structure and enhancing starch properties. However, further research is needed to tailor the approach based on the specific properties of the raw material., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The current research emphasis on identifying unconventional starch sources with varied properties to broaden industrial applications. The focus of this research is on the search for alternative sources of starch with different properties in order to expand their potential use in the industrial sector. Starch was extracted from Trapa natans and Nelumbo nucifera and analyzed for their physicochemical and functional properties. They had similar protein (0.35 %) and ash contents, but the nitrogen-free extract was slightly higher in Nelumbo starch (87.58 %) than in Trapa starch (85.09 %). The amylose and amylopectin contents were 23.89 % and 76.11 % in Trapa starch and 15.70 % and 84.30 % in Nelumbo starch, respectively. Fourier-transform infrared spectroscopy identified both as polysaccharides. The characteristic absorption bands assigned to the stretching of OH groups (3324 cm -1 ; 3280 cm -1 ), the asymmetric and symmetric stretching of aliphatic chain groups (2925 cm -1 ; 2854 cm -1 ), the bending vibration of CHO groups (1149 cm -1 ; 1144 cm -1 ) were present in both the starch samples, with the exception of CH 3 which could not be detected in Trapa natans starch. X-ray diffraction confirmed hexagonal and orthorhombic crystal structures in Nelumbo nucifera and Trapa natans starch. Scanning electron microscopy revealed a smooth oval and a rough cuboidal shape for lotus and chestnut starch, respectively. Rheological analysis showed that both starch solutions exhibited gel behavior, with Trapa showing stronger gel behavior after the crossover point. These results suggest potential applications in various industries, including the food industry and beyond., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Starch is a natural, abundant, renewable and biodegradable plant-based polymer that exhibits a variety of functional properties, including the ability to thicken or gel solutions, form films and coatings, and act as encapsulation and delivery vehicles. In this review, we first describe the structure of starch molecules and discuss the mechanisms of their interactions with guest molecules. Then, the effects of starch-guest complexes on gelatinization, retrogradation, rheology and digestion of starch are discussed. Finally, the potential applications of starch-guest complexes in the food industry are highlighted. Starch-guest complexes are formed due to physical forces, especially hydrophobic interactions between non-polar guest molecules and the hydrophobic interiors of amylose helices, as well as hydrogen bonds between some guest molecules and starch. Gelatinization, retrogradation, rheology and digestion of starch-based materials are influenced by complex formation, which has important implications for the utilization of starch as a functional and nutritional ingredient in food products. Controlling these interactions can be used to create novel starch-based food materials with specific functions, such as texture modifiers, delivery systems, edible coatings and films, fat substitutes and blood glucose modulators.

Over the past decades, dynamic high-pressure treatment (DHPT) executed by high-pressure homogenization (HPH) or microfluidization (DHPM) technology has received humongous research attention for starch macromolecule modification. However, the studies on starch multi-level structure alterations by DHPT have received inadequate attention. Furthermore, no review comprehensively covers all aspects of DHPT, explicitly addressing the combined effects of both technologies (HPH or DHPM) on starch's structural and functional characteristics. Hence, this review focused on recent advancements concerning the influences of DHPT on the starch multi-level structure and techno-functional properties. Intense mechanical actions induced by DHPT, such as high shear and impact forces, hydrodynamic cavitation, instantaneous pressure drops, and turbulence, altered the multi-level structure of starch for a short duration. The DHPT reduces the starch molecular weight and degree of branching, destroys short-range ordered and long-range crystalline structure, and degrades lamellar structure, resulting in partial gelatinization of starch granules. These structural changes influenced their techno-functional properties like swelling power and solubility, freeze-thaw stability, emulsifying properties, retrogradation rate, thermal properties, rheological and pasting, and digestibility. Processing conditions such as pressure level, the number of passes, inlet temperature, chamber geometry used, starch types, and their concentration may influence the above changes. Moreover, dynamic high-pressure treatment could form starch-fatty acids/polyphenol complexes. Finally, we discuss the food system applications of DHPT-treated starches and flours, and some limitations., Competing Interests: Declaration of competing interest Authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Taro (Colocasia esculenta) flour is a viable carbohydrate alternative and a functional additive for food formulation; however, different taro varieties may possess distinct characteristics that may influence their suitability for food production. This study evaluated the nutritional, physicochemical, and functional properties of flours from five Hawaiian taro varieties: Bun-Long, Mana Ulu, Moi, Kaua'i Lehua, and Tahitian. Tahitian, Bun-long, and Moi had high total starch contents of 40.8, 38.9, and 34.1 g/100 g, respectively. Additionally, Moi had the highest neutral detergent fiber (25.5 g/100 g), lignin (1.39 g/100 g), and cellulose (5.31 g/100 g). In terms of physicochemical properties, Tahitian showed the highest water solubility index (33.3 g/100 g), while Tahitian and Moi exhibited the two highest water absorption indices (5.81 g/g and 5.68 g/g, respectively). Regarding functional properties, Tahitian had the highest water absorption capacity (3.48 g/g), and Tahitian and Moi had the two highest oil absorption capacities (3.15 g/g and 2.68 g/g, respectively). Therefore, the flours from these Hawaiian taro varieties possess promising characteristics that could enhance food quality when used as alternative additives in food processing., (© 2024 Institute of Food Technologists.)

In this study, we aimed to use electrical impedance spectroscopy (EIS) to assess the freeze-damage level of starches from potato tubers treated with multiple freezing-thawing (FT) cycles. The results showed that the relationship between the physicochemical properties of starches and the impedance characteristics of starch paste is temperature-dependent. As the temperature rises to 70-90 °C, the impedance modules show a significant correlation with the amylose and mineral contents, gelatinization and pasting properties, short-range ordered structure, relative crystallinity, and damage level within the range of 10-1 MHz (p < 0.01). This could be because FT leads to a reduction in amylose and ion content. Compared to a high level of freeze-damaged starch (FDS), a low level of FDS has less amylopectin and more amylose. Additionally, the ions could be typically evenly distributed throughout the unbranched linear amylose structure in starch paste. At the peak gelatinization temperature, the starch paste made from a low level of FDS exhibits a weakened network structure, allowing more unbound water for ion movement and enhancing electric conduction. In conclusion, EIS can predict the damage level and properties of FDS, which can benefit the frozen starchy food industry., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Recently, non-conventional sources of starch have attracted attention due to their potential to provide cost-effective alternatives to traditional starch. Among non-conventional starches, loquat (Eriobotrya japonica) seed starch is an emerging source of starch consisting of the amount of starch (nearly 20 %). It could be utilized as a potential ingredient due to its unique structure, functional properties, and novel applications. Interestingly, this starch has similar properties as commercial starches including high amylose content, small granule size, and high viscosity and heat stability, making it an attractive option for various food applications. Therefore, this review mainly covers the fundamental understanding of the valorization of loquat seeds by extracting the starch using different isolation methods, with preferable structural, morphological, and functional properties. Different isolation and modification methods (wet milling, acid, neutral and alkaline) are effectively used to obtain higher amounts of starch are revealed. Moreover, insight into various analytical techniques including scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction used to characterize the molecular structure of the starch are discussed. In addition, the effect of shear rate and temperature on rheological attributes with solubility index, swelling power, and color is revealed. Besides, this starch contains bioactive compounds that have shown a positive impact on the enhancement of the shelf-life of the fruits. Overall, loquat seed starches have the potential to provide sustainable and cost-effective alternatives to traditional starch sources and can lead to novel applications in the food industry. Further research is needed to optimize processing techniques and develop value-added products that can be produced at a large scale. However, there is relatively limited published scientific evidence on the structural and morphological characteristics of loquat seed starch. Thus, in this review, we focused on different isolation techniques of loquat seed starch, its structural and functional characteristics, along with potential applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Sorbitol as a plasticizer is easily crystallized from starch film, resulting in the reduction in plasticizing effect. To improve the plasticizing performance of sorbitol in starch films, mannitol, an acyclic hexahydroxy sugar alcohol, was used to cooperate with sorbitol. The effects of different ratios of mannitol (M) to sorbitol (S) as a plasticizer on mechanical properties, thermal properties, water resistance and surface roughness of sweet potato starch films were investigated. The results showed that the surface roughness of starch film with M:S (60:40) was the smallest. The number of hydrogen bonds between plasticizer and starch molecule was proportional to the mannitol content starch film. With the decrease of mannitol contents, the tensile strength of starch films gradually decreased except for M:S (60:40). Moreover, the transverse relaxation time value of starch film with M:S (100:0) was the lowest, indicating that it had the lowest degree of freedom of water molecules. Starch film with M:S (60:40) is the most effective in delaying the retrogradation of starch film. This study offered a new theoretical basis that different ratios of mannitol to sorbitol improve different performances of starch films., Competing Interests: Declaration of competing interest We confirm that there are no any conflicts of interest with respect to this publication and there has been no financial support for this article that could influence the outcome., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Seeds represent a potential source of starch, containing at least 60-70% of total starch, however many of them are treated as waste and are usually discarded. The review aim was to analyze the characteristics, functional properties, and potential applications of native and modified starches from underutilized seeds such as Sorghum bicolor L. Moench (WSS), Chenopodium quinoa, Wild. (QSS), Mangifera indica L. (MSS), Persea americana Mill. (ASS), Pouteria campechiana (Kunth) Baehni (PCSS), and Brosimum alicastrum Sw. (RSS). A systematic review of scientific literature was carried out from 2014 to date. Starch from seeds had yields above 30%. ASS had the higher amylose content and ASS and RSS showed the highest values in water absorption capacity and swelling power, contrary to MSS and PCSS while higher thermal resistance, paste stability, and a lower tendency to retrograde were observed in MSS and RSS. Functional properties such as water solubility, swelling power, thermal stability, low retrogradation tendency, and emulsion stability were increased in RSS, WSS, QSS, and MSS with chemical modifications (Oxidation, Oxidation-Crosslinking, OSA, DDSA, and NSA) and physical methods (HMT and dry-heat). Digestibility in vitro showed that WSS and QSS presented high SDS fraction, while ASS, MSS, PCSS, and HMT-QSS presented the highest RS content. Native or modified underutilized seed starches represent an alternative and sustainable source of non-conventional starch with potential applications in the food industry and for the development of healthy foods or for special nutritional requirements., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Qingke protein rich in restricted amino acids such as lysine, while the uncoordination of ratio of glutenin and gliadin in Qingke protein has a negative impact on its processing properties. In this study, the effect of multiple-frequency ultrasound combined with transglutaminase treatment on the functional and structural properties of Qingke protein and its application in noodle manufacture were investigated. The results showed that compared with the control, ultrasound-assisted transglutaminase dual modification significantly increased the water and oil holding capacity, apparent viscosity, foaming ability, and emulsifying activity index of Qingke protein, which exhibited a higher storage modulus G' (P < 0.05). Meanwhile, ultrasound combined with transglutaminase treatment enhanced the cross-linking degree of Qingke protein (P < 0.05), as shown by decreased free amino group and free sulfhydryl group contents, and increased disulfide bond content. Moreover, after the ultrasound-assisted transglutaminase dual modification treatment, the fluorescence intensity, the contents of α-helix and random coil in the secondary structure of Qingke protein significantly decreased, while the β-sheet content increased (P < 0.05) compared with control. SDS-PAGE results showed that the bands of Qingke protein treated by ultrasound combined with transglutaminase became unclear. Furthermore, the quality of Qingke noodles made with Qingke powder (140 g/kg dual modified Qingke protein mixed with 860 g/kg extracted Qingke starch) and wheat gluten 60-70 g/kg was similar to that of wheat noodles. In summary, multiple-frequency ultrasound combined with transglutaminase dual modification can significantly improve the physicochemical properties of Qingke protein and the modified Qingke proteins can be used as novel ingredients for Qingke noodles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The gelatinization, pasting, and retrogradation of starch influence texture, quality, and shelf-life attributes of many foods. The purpose of this work was to document the effects of a 50:50 glucose:fructose (glc:fru) mixture and sucrose solutions on these starch traits to provide a fundamental basis to explain the different texture and shelf-life attributes of baked goods formulated with these sugars. Differential scanning calorimetry, rapid visco analyzer, and oscillatory rheometry were used to quantify the effects of glucose, fructose, glc:fru mixture, and sucrose at different concentrations (0% to 60% w/w), on the gelatinization temperature, pasting, and retrogradation properties of wheat starch. Distinct differences were found between the effects of sucrose and those of the monosaccharides including the glc:fru mixture. Sucrose elevated T gel and pasting temperature most and decreased other RVA parameters compared to the monosaccharides as concentration increased. Fructose and the glc:fru mixture promoted amylopectin retrogradation, while retrogradation was inhibited in sucrose and glucose solutions. The glc:fru mixture had similar effects on starch properties compared to fructose under static measurement conditions (DSC), and the effects were in between those of glucose and fructose under dynamic conditions when shear was applied (RVA and rheology). These effects are explained by the phase separation and/or solute partitioning of the monosaccharide constituents of the glc:fru mixture. Sugar solution physicochemical properties correlated strongly with starch gelatinization and retrogradation. The results substantiate the important relationship between sugar physicochemical properties and solution dynamics with starch thermal properties, which in turn affect the texture and structure of starch-containing food products. PRACTICAL APPLICATION: The quality attributes of starch-containing baked goods are influenced by how different amounts and types of sugars affect starch cooking properties. The underlying mechanisms of the different sugar effects involve solution viscosity, intermolecular hydrogen bonding, and phase separation. Substituting one sugar for another has less effect on these starch properties in products with lower sugar concentrations than in products with more sugar. Mixtures of sugars behave differently than single sugars in different conditions due to phase separation. Baked goods made with glucose:fructose mixtures in place of sucrose likely have higher amounts of gelatinized starch and increased firmness (i.e., staling or retrogradation) over time., (© 2022 The Authors. Journal of Food Science published by Wiley Periodicals LLC on behalf of Institute of Food Technologists.)

The objective of this study was to obtain and characterize flours and starches from the avocado seeds of Hass and landrace cultivars. The morphological, physical-chemical, structural, thermal and rheological characteristics were evaluated. The flour yield of the Hass and landrace cultivars was 41.56 to 46.86% ( w / w ), while for starch, it was 35.47 to 39.57% ( w / w ) (cv. Hass and landrace, respectively). Scanning electron microscopy (SEM) revealed the presence of oval starch granules and other particles in flour, in contrast to flours, starches showed lower ash, proteins and lipids content. However, the amylose content was higher in starches (42.25-48.2%). Flours showed a higher gelatinization temperature ( T p = 73.17-73.62 °C), and their starches presented greater gelatinization enthalpy (∆ H gel = 11.82-13.43 J/g). All samples showed a B-type diffraction pattern, and the crystallinity was higher in the flours. The rheological analysis (flow curves and viscoelastic tests) evidenced a pseudoplastic ( n = 0.28-0.36) behavior in all samples analyzed, but the consistency index ( k ) was higher in starches. In general, the flours and starches from avocado seeds presented interesting proximal, thermal and functional properties for possible application in food systems, and these findings could contribute to the revaluation of this by-product.

The study aimed to develop pre-gelatinized starch-based orally disintegrating films (ODFs) containing catechin/β-cyclodextrin (CAT/β-CD) complex and to evaluate the influence of the complex on the physicochemical properties of the ODFs. SEM images showed that a compacter and more homogeneous ODFs were formed due to interactions between starch matrix and CAT/β-CD. FTIR spectra demonstrated that the interactions between starches or starch and CAT/β-CD were enhanced by hydrogen bonds. Thermal stability of ODFs was improved by incorporating CAT/β-CD, its peak decomposition temperature was enhanced from 310.74 to 321.83 °C. Tensile strength was increased from 11.597 ± 0.153 to 22.172 ± 0.752 MPa, while elongation at break decreased by from 11.233% ± 1.079% to 3.633% ± 0.058%. The prepared ODFs have an acceptable in vitro disintegration time, which were between 9.03 ± 0.79 s and 42.23 ± 1.76 s. Antimicrobial test showed that ODFs incorporating CAT/β-CD inhibited the growth of S. aureus and S. mutans successfully. The limited release of CAT molecules from the ODFs was also found. In addition, the ODFs have excellent antioxidant capacity. Its antioxidant activity remained at around 70% after 28 days of storage. The study indicated that the combination of ODFs and β-CD complex have a high potential for the delivery of natural active ingredients., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Understanding how starch constituent in frozen dough affected bread quality would be valuable for contributing to the frozen products with better quality. To elucidate the underlying mechanism, starch was fractionated from multiple freezing-thawing (F/T) treated dough and reconstituted with gluten. Results showed that F/T treatment destructed the molecular and supramolecular structures of starch, which were more severe as the F/T cycle increasing. These structural disorganizations made water molecules easier to permeate into the interior of starch granules and form hydrogen bonds with starch molecular chains, which elevated the peak, breakdown, setback and final viscosity of starch paste. In addition, F/T treatment resulted in decreased specific volume (from 1.54 to 0.90 × 10 3 m 3 /Kg) and increased hardness (from 42.98 to 52.31 N) for steamed bread. We propose the strengthened water absorption ability and accelerated intra- and inter-molecular rearrangement of starch molecules and weak stability of "starch-gluten matrices" would allow interpreting deteriorated bread quality., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Waxy hull-less barley kernels and their isolated starches were exposed to different microwave conditions (power 640, 720, and 800 W, time 60, 120 and 180 s) and changes in morphology, particle size, digestibility, rheological properties, and molecular structure were measured and analyzed. Microwave treatment caused roughness and deformation of granular surfaces, and an increase in granule size. After treatment, the in vitro digestibility of starch was increased, i.e., the RDS increased, but the RS decreased. Microwave treatment decreased the K values of the in-kernel MWI WHBS. Dynamic rheological results showed that the in-kernel MWI WHBS pastes had lower T G'max , and higher G' max , G' 90 °C , G' 25 °C , G' 0.1Hz and G' 20Hz after treatment. The chain-length distribution did not significantly change after microwave treatment. However, the results for molecular size distributions showed that the peaks of amylopectin (R h  = ~100 nm) shifted left and right, indicating that the molecular volume might become smaller or larger under different processing conditions. The primary effects of microwave treatment may be loosening the molecular structure and cutting main chains of amylopectin., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Ramie root is an underutilized starch source. In this study, eight ramie varieties were investigated for starch properties. Starch content ranged from 18.6% to 50.1% in dry root. Starches from different varieties showed similar morphology including ellipsoidal, spherical and truncated granules with size D[4,3] from 10.1 to 14.1 μm. Starch had amylose content from 20.8% to 28.5%. All ramie varieties had B-type starches with relative crystallinity from 24.8% to 27.1%, ordered degree from 0.724 to 0.897 and lamellar thickness from 9.1 to 9.6 nm. Starches had gelatinization peak temperature from 70.5 to 73.8 °C and enthalpy from 14.9 to 15.8 J/g. Starches had swelling power and water solubility from 27.9 to 31.9 g/g and from 11.7% to 15.5%, respectively, at 95 °C, and exhibited different pasting properties with breakdown viscosity from 36 to 377 mPa s and setback viscosities from 1295 to 1863 mPa s. Starch pastes exhibited pseudoplastic behavior and different rheological properties. Native, gelatinized and retrograded starches had resistant starch from 81.7% to 83.9%, from 1.7% to 5.1% and from 5.6% to 13.3%, respectively. The eight varieties were divided into 3 groups according to starch properties. This study is helpful for selecting suitable ramie variety as starch source., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this paper, the impact of different substitution levels of cress seed gum (CSG, 0, 5, 10, and 15%) and sucrose (SUC, 0, 5, and 10%) on the rheological properties, textural attributes, syneresis, FTIR and microstructure of native wheat starch (NWS, 4%) gel was investigated. According to the rheological tests, the NWS-CSG and NWS-CSG-SUC gels showed thixotropic behavior and all the samples exhibited shear-thinning flow behavior. Increasing the CSG substitution level up to 15% elevated the apparent viscosity, consistency coefficient whereas the SUC substitution with NWS reduced these values. The higher apparent viscosity, consistency coefficient, and stronger pseudoplastic behavior were obtained for NWS-CSG-SUC gel than NWS gel. The addition of CSG greatly decreased hardness and consistency from 140 to 55.5 g and from 6.9 to 3.0 mJ, respectively during storage at 4 °C for 14 days; while in the presence of SUC these values slightly decreased. After storage, syneresis of NWS and NWS-10%SUC gels increased by 46.78% and 32.11%, respectively; whereas it decreased 19.88% for NWS-15%CSG gel. The SEM images showed that the mixed gels had a denser structure with a smaller pore size. The results indicated that CSG had positive effect in modifying the properties of NWS-SUC mixed gels., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Unripe banana fruit of Musa acuminata (Musa AAA; Hom Khieo) and Musa sapientum L. (Musa ABB; Namwa) growing in Chiang Rai (Thailand) were used for extraction. The yield of the starches was 16.88% for Hom Khieo (HK) and 22.73% for Namwa (NW) based on unripe peeled banana fruit. The amylose contents of HK and NW were 24.99% and 26.23%, respectively. The morphology of starch granules was oval shape with elongated forms for large granules and round shape for small granules. The HK and NW showed B-type crystalline structure and the crystallinities were 23.54% and 26.83%, respectively. The peak temperature of gelatinization was around 77 °C and the enthalpy change (ΔH) was 3.05 and 7.76 J/g, respectively. The HK and NW banana starches showed 1.27 ± 0.12 g/g and 1.53 ± 0.12 g/g water absorption capacity, and 1.22 ± 0.11 g/g and 1.16 ± 0.12 g/g oil absorption capacity, respectively. The swelling power of the banana starches was 17.23 ± 0.94 g/g and 15.90 ± 0.15 g/g, respectively, and the percentage of solubility in water showed 26.43 ± 2.50 g/g and 20.54 ± 0.94 g/g, respectively. The banana starches showed very poor flow character. The HK and NW starches have the potential to be used in powder base preparations with no effect on the sensory texture of the product at 15% w / w maximum.

Background: The effect of high-pressure homogenization (HPH) on the rheological and thermal properties, water retention capacity (WRC), morphology and in vitro digestion of wheat starch was evaluated. Starch suspensions (50 g kg -1 , w/w) were treated at increasing pressures (up to 100 MPa) and numbers of cycles (up to 5) to generate a wide range of energy densities (70-500 MJ m -3 ) delivered to the sample during processing., Results: High-pressure homogenization induced a partial starch gelatinization confirmed by higher digestibility. Gelatinization degree (GD) was between 13% and 83%, causing a wide range of functional properties. High-pressure homogenization-treated starch samples showed WRC values of 810-1910 g kg -1 . Storage modulus (G') and complex viscosity (η * ) of starch dispersions were almost two and three times higher than the control at 13% and 83% GD, respectively. Positive linear relationships between GD (R = 0.98, P < 0.001), WRC (R = 0.87, P < 0.05), or rheological parameters (R = 0.89÷0.90, P < 0.01) and energy density of HPH treatments were found., Conclusion: High-pressure homogenization treatment represents a promising technology to obtain wheat starch with tailored rheological properties and digestibility, which allows the texture and glycemic response of food products to be adjusted. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

This study was performed to investigate the influence of Lepidium perfoliatum seed gum (LPSG) and Alyssum homolocarpum seed gum (AHSG) on functional properties of wheat starch. Various concentrations of gums (0.25%, 0.5%, 0.75%, and 1% dry starch weight basis) were added to wheat starch, and their influences on water absorption, pasting properties, gel strength, freeze-thaw stability and color parameters were investigated. The results showed that both gums improved water absorption, freeze-thaw stability, pasting parameters, gel hardness, gumminess, and chewiness whereas springiness was not affected and cohesiveness was decreased by the incorporation of gums and LPSG more effective than AHSG. Color parameters were also affected by the concentration of gums. The L value decreased whereas a value and b value increased in the presence of both gums. However, the changes were more obvious in samples containing LPSG. PRACTICAL APPLICATION: Starch is one of the most important carbohydrate materials in the food industry. However, native starch has shortcomings, such as sensitivity to shear or syneresis that limit its applications in food processing. Incorporation of hydrocolloids is an effective strategy to improve functional properties of starch. LPSG and AHSG are two novel sources of hydrocolloids which can be used to modify the properties of starch in food products., (© 2021 Institute of Food Technologists®.)

The nitrogen (N) influences the growth of sweet potato. However, it is unclear whether the different levels of N can affect starch physicochemical properties. In this study, 9 different colored-fleshed sweet potato varieties were planted in the same field with additional N fertilizer treatment of 0, 15 and 30 kg/ha. The physicochemical properties of starches from root tubers were measured. With increasing N level, the amylose content decreased in yellow-fleshed variety Sushu 16 and increased in white-fleshed variety Sushu 29 and purple-fleshed varieties Ningzishu 1 and 4, but did not significantly change in other varieties. The starch size decreased in purple-fleshed variety Ningzishu 1 and white-fleshed varieties Sushu 28 and Sushu 29 with increasing N treatment, but first increased then decreased in yellow-fleshed variety Sushu 16 and first decreased then increased in white-fleshed variety Sushu 24 and yellow-fleshed variety Sushu 25. The different levels of N treatment had no influence on protein content, crystalline structure, and gelatinization enthalpy of starch. The effects of N treatment on gelatinization temperatures and pasting viscosities of starches were determined by varieties and genotype backgrounds of sweet potato. The PLSR and PLS-DA were also carried out based on structural, thermal, and pasting parameters of starches., (Copyright © 2020. Published by Elsevier B.V.)

The objective of this research was to investigate the effect of different ratios of grapefruit seed extract (GFSE) on functional properties of bionanocomposite (BNC) films prepared with corn starch (CS) incorporated with chitosan (CH)-nanoclay. Experimental results exhibited that the addition of GFSE properly dispersed with CS combined with CH bionanocomposite films. The presence of GFSE from 0 to 1.5% v/v exhibited increase in crystallinity and TS while decease in EB, FS and WVP. Furthermore, an addition of 2%v/v GFSE revealed decrease in its physical properties. When bread samples were packed, synthetic plastic exhibited the proliferation of fungal growth in 6 days, whereas CS/CH/1.5% v/v GFSE bionanocomposite film exhibited the same for at least 20 days. This study presents that CS/CH/1.5% v/v GFSE nanoclay film could potentially be useful for novel eco-friendly active packaging for confectionary industries to extend the shelf life to maintain its quality and safety of food products., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The aim of this paper was to evaluate the effect of thermal treatment and UV irradiation on structural and physicochemical properties of octenyl succinate (OS) maize starches differing in content of OS groups (0.76%-2.38%). X-ray diffraction (XRD), gel permeation chromatography (GPC), and electron paramagnetic resonance (EPR) spectroscopy were used to estimate structural characteristics of octenyl succinate starches and their physically treated counterparts. Starch functional properties were also determined. XRD spectra and hydrodynamic volume distribution revealed that growth of octenyl succinate groups' content resulted in stabilization of starch structure, which was confirmed by processes of radical formation, stimulated by thermal and UV treatments. It was found, on the basis of measurements of water binding capacity, water solubility and intrinsic viscosity, that OSA addition changed physicochemical properties of starch and influenced the course of physical modifications. It was established that temperature affected starch properties to a greater extent than UV., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The continued increase in Nigeria's rice production makes product diversification very fitting, even to underutilized indigenous/local varieties. Further, rice converted to malt can bring about useful products like syrup with enhanced characteristics. In this context, a comparative study involving some functional properties of syrup from malted and unmalted rice of different varieties was carried out. Syrup from either filtered or centrifuged starch hydrolysates of enzyme hydrolyzed rice (malted/unmalted) flours gave rise to filtered unmalted (FUHR), filtered malted (FMHR), centrifuged unmalted (CUHR), and centrifuged malted hydrolyzed rice (CMHR) groups. From these, functional properties, that is, pH, total soluble proteins (TSP), total dissolved solids (TDS), total solids (TS), dextrose equivalent (DE), titratable acidity (TA), apparent brix (°B), specific gravity (SG), syrup yield (SY), and some minerals [calcium (Ca), iron (Fe), magnesium (Mg), and zinc (Zn)] were determined. Results showed syrup from malted with significantly higher (P < 0.05) SY, Brix, pH, SG, TS, TDS, and TSP, but significantly lower (P < 0.05) TA, DE, and mineral contents (Ca, Zn, Fe, and Mg) over the unmalted group. Some significant interactions (P < 0.05) were found, between rice variety, treatment and separation method (TS, TDS, DE, Brix, SY, and Ca), rice variety and treatment (TSP, Zn, Mg, and Fe), as well as rice variety and separation method (TSP, pH). In addition, some positive and negative significant (P < 0.05) correlations between the studied functional properties were found. Overall, malting and processing methods can influence the functional properties of rice syrup-an acceptable specialty ingredient for brewing/beverage production. PRACTICAL APPLICATION: Through the application of exogenous enzymes, rice syrup has been successfully produced from locally bred/improved rice varieties commercially available in Nigeria. By comparing some functional properties of syrup from malted and/or unmalted rice, the current research provides useful evidence that locally available rice varieties are potential candidates for product diversification to the food/brewing, pharmaceuticals, and other industries, not only in Nigeria but also in the West Africa subregion., (© 2020 Institute of Food Technologists®.)

Structure-function relationships of starch isolated from eight cultivars of foxtail millets grown in China were investigated. The starch granules were polygonal with diameters between 5 μm and 10 μm. The amylose content ranged from 16.8% to 26.8%, and the relative crystallinity and the full width at half maximum (FWHM) of the Raman band at 480 cm -1 varying between 33.2% and 36.4% and 15.72 to 15.91, respectively. There were only small differences in amylopectin chain length distribution of the eight foxtail millet starches. Significant differences were noted in swelling power, gelatinization, pasting, gel textural properties of starches, but not in vitro enzymic digestibility. Correlation analysis results showed that amylose content and chain length distribution of amylopectin were more important determinants of functional properties of starch than the structural order of the starch granules., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The effects of pressure and temperature on the gelatinization properties of wheat starch were investigated. The long-range crystallinity and short-range molecular order were gradually destroyed under both conditions as the degree of gelatinization (DG) increased. With increasing DG, differential scanning calorimetry (DSC) onset (T o ), peak (T p ) and conclusion temperatures (T c ) increased for the heat-gelatinized samples but did not change greatly for the pressure-gelatinized samples. At similar DG, pressure-gelatinization resulted in less granule swelling than heat-gelatinization. Lower degree of both heat- and pressure-gelatinization resulted in increased pasting viscosities and gel texture parameters, whereas the opposite was noted at higher DG. We conclude that pressure and heat induced starch gelatinization in different ways, resulting in different gel texture properties. Pressure-gelatinization disrupted both less stable and more stable crystallites, whereas less stable crystallites were preferentially disrupted during heat-gelatinization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this study, 6 very small granule starches (VSGSs) were isolated from endosperms of dicotyledon Amaranthus cruentus, Agriophyllum squarrosum, Chenopodium quinoa, Euryale ferox, Mirabilis jalapa, and Vaccaria hispanica. Their morphologies and physicochemical properties were investigated. Most VSGSs with granule size <3 μm were spherical or polygonal, and their apparent amylose contents ranged from 19.4 to 33.1% with A. cruentus starch the lowest and E. ferox starch the highest. All VSGSs had the same A-type crystalline structure with relative crystallinities from 23.3 to 29.6%. Though 6 VSGSs had slight differences in short-range ordered structure and lamellar repeat distance, their lamellar peak intensities exhibited significant differences. The gelatinization temperatures showed significant differences among 6 VSGSs with C. quinoa starch the lowest and M. jalapa starch the highest. The 6 VSGSs had significantly different pasting viscosities with peak viscosities from 1887 to 4579 mPa s, hot viscosities from 1704 to 3479 mPa s, breakdown viscosities from 56 to 1170 mPa s, final viscosities from 2419 to 4811 mPa s, and setback viscosities from 715 to 1821 mPa s. The digestion properties of starches were significantly different among 6 VSGSs. The above results could provide some references for applications of these VSGSs., (Copyright © 2020 Elsevier B.V. All rights reserved.)

There is an emerging interest in the development of biomaterial-based nanoparticles. Recent studies have shown that starch nanoparticles (SNP's) could be prepared from starch granules with unique functional properties. Starch nanoparticles/nanocrystals can be prepared by acid or enzymatic hydrolysis, regeneration, mechanical treatments, and combined enzymatic and precipitation methods. Different approaches including chemical, physical, and enzymatic methods have been used to modify the SNP's to enhance and diversify their applications profile. SNP's have found novel applications in various food systems such as reinforcement materials in nanocomposites, encapsulating agents, emulsion stabilisers, and carrier and releasing agents., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The effects of the addition of edible gums (xanthan gum (XG), flaxseed gum (FG), konjac glucomannan (KGM) or tamarind seed gum (TSG)) on texture, gelatinisation and retrogradation of selected starches were investigated. XG and KGM significantly (p < 0.05) reduced syneresis of rich starch gels, from 62.5% to 13.1% and 62.5% to 21.2%, respectively. Moreover, the addition of gums resulted in softer binary gels, the hardness of lotus root starch was reduced from 39.07 to 14.08 g with the increase in XG content. Additionally, FG and TSG significantly increased the peak viscosity of mung bean starch (MBS) gels from 4372 to 10,285 cp. This facilitated the use of MBS gels as thickeners in foods. Binary gels improved the heat stability of starch gels, thus, widening its application in the preparation of baked foods. Binary gels could be used as additives in food production to improve the overall quality of foods., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Limited studies have been reported on the interaction of elephant foot yam (EFY) starch and hydrocolloids. Hence the present study investigated the effect of hydrocolloids (agar-agar, AAG and xanthan gum, XG) concentration (0.5, 1, 1.5 and 2%) on pasting, rheological, thermo-functional and morphological properties of EFY starch. The increase in concentration reduced the swelling index and enhanced the solubility. Peak, holding, break down and set back viscosity was highest at 2% XG than AAG. Dynamic storage modulus (G') was higher than loss modulus (G″) within frequency range with an increase in hydrocolloids concentration. Pasting temperature reduced from 77.20 to 49.7 °C (AAG) and 77.20 to 61.56 °C (XG). FTIR exhibited differences in peak absorbance and broadness of OH and CO stretching at 3400-3200 cm -1 and 1260-1000 cm -1 upon hydrocolloids' addition. Increased AAG concentration reduced the peak temperature of gelatinization and retrogradation of EFY starch. The effect of hydrocolloids and their concentrations on the higher binding of EFY starch molecules and crystallinity has also been supported by SEM images. These results show that EFY starch with hydrocolloids can be used as a thickener. Its good binding ability may be explored for the possible applications in bakery industry and for the development of edible packaging film., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The present study isolated starch from corn and sorghum grains through wet milling procedure. Sorghum starch is considered an alternative to corn starch in future, due to similar functional properties. However, agronomically sorghum is a cheap input cost crop compared to sorghum and can grow in drought hit areas. Lactic acid and citric acid modifications along with heat-moisture treatments were performed on both sorghum and corn grains followed by their comparison in terms of functional, textural, thermal, pasting and digestibility characteristics. For both corn and sorghum starches, the resistant starch increased after chemical modifications. The RS content of acid and acid-heat moisture treated starches were in the range of 77.9-90%, significantly higher than those of native starches (64.6-68.8%). The modifications increased the gelatinization temperature, decreased the peak and cold paste viscosity of starches. Chewiness significantly reduced after lactic and citric acid treatment along with heat-moisture treatments. The crystallinity to amorphous ratio measured through Fourier Transform infrared reduced after all chemical treatments. Percent light transmittance was further reduced after heat-moisture treatments, however the effect on corn starch was more pronounced i.e. it declined from 16.5 to 5.2%. The acid-heat moisture treatments had considerably lowered the glycemic index of starch. The GI reduced from 74 to 49.7 and 60 to 48.5 when treated with acid in the presence of heat and moisture. Thus, these starches could be used in production of low-calorie foods., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study aimed to investigate the influence of sun-drying after spontaneous or back-slopping fermentation on waxy maize starch (WMS) properties by thermal and pasting properties, water activity and chemical composition, swelling power and solubility, and morphological characteristics. The microbial metabolism affected chemical composition, as back-slopping fermentation reduced the time for achieving 4% of total acidity from 27 to 7 days. WMS was susceptible to surface degradation by the fermentation process. The kind of fermentation did not change the gelatinization parameters, viscosity breakdown and oil solubility. FS decreased peak viscosity, final viscosity and setback values, while increasing peak time and paste temperature values, showed more statistical differences with respect to WMS than BSF. Back-slopping fermentation can speed up the process of the modification of waxy maize starch, and change its functional properties, which can extend the WMS industrial applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Potato starch was pre-treated with CaCl 2 solutions prior to modification with octenyl succinic anhydride (OSA). Starch pre-treated with 1.0 M CaCl 2 showed higher degree of substitution (DS) and reaction efficiency (RE) on OSA modification, whereas pre-treatment with CaCl 2 solutions at 0.05 M, 0.1 M and 0.5 M had no effect on DS and RE. CaCl 2 pre-treatment decreased the swelling power, paste clarity, peak viscosity (PV), breakdown (BD) and some textural parameters of potato starch, with the effects being greater at higher concentrations of CaCl 2 . Pre-treatment with 1.0 M CaCl 2 caused a small disruption to starch crystallinity and granule morphology. OSA modification significantly decreased the textural parameters, PV, BD, relative crystallinity, swelling power, gelatinization temperatures and enthalpy of potato starch, but it increased the paste clarity and emulsifying activity. OSA-1.0 M-starch showed improved functional properties over OSA-starch, indicating that CaCl 2 pre-treatment provides advantages for improving the functional characters of succinylated starch., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study, moisture, steam-temperature and time conditions were optimised in relation to functional properties of cassava flour and starch. The optimal conditions for cassava flour were 15% moisture, 120 °C and 1 bar for 10 min and for cassava starch were 19% moisture, 120 °C and 1 bar for 20 min. Structural, physicochemical, viscoelastic and thermal characteristics of cassava flour and starch upon the optimal steam-heat-moisture treatments were examined Volume-based diameter (D (4.3) ) of cassava flour granules reduced (107.87 to 42.94 μm) and cassava starch granules increased (17.67 to 50.88 μm) when subjected to optimal steam-heat-moisture treatments. The optimal steam-heat-moisture treatments had no effect on the crystal patterns of cassava flour and starch (A-type), nonetheless, relative crystallinity of cassava flour was increased (34 to 59%) and cassava starch was decreased (32 to 27%). Increments in swelling power (17.24 to 19.07 g/g) and peak viscosity (6377 and 7330 cP) and, reductions in solubility and loss factor (tanδ) were ensued by the optimal steam-heat-moisture treatment of cassava starch. Both optimal steam-heat-moisture treatments of cassava flour and starch had increased thermal stability but reduced breakdown viscosity, setback viscosity (528 to 230 cP and 1259 to 938 cP, respectively) and gelatinisation enthalpy., (Copyright © 2018. Published by Elsevier B.V.)

In this study, starches from diverse botanical sources (arrowroot, cassava, Chinese yam, fern root, kidney beans, lotus seed, taro, and water chestnut) were isolated and examined for morphological, pasting, thermal, and physico-chemical characteristics in order to distinguish their end use potential. Among isolated starches significant differences (p < 0.05) were observed in gelatinization temperatures, morphology, color, pasting, and functional properties. Amylose content of isolated starches varied between 17.12% and 35.62%. X-ray diffraction pattern of isolated starches displayed A-type (arrowroot, cassava, corn, and kidney bean), B-type (potato) and C-type (water chestnut, taro, Chinese yam, fern root, and lotus seed) crystalline pattern. The FT-IR spectra of isolated starches confirmed their carbohydrate nature. Furthermore, the current study affords information for the exploitation of isolated starches from the diverse botanical sources cultivated in China that would be convenient for commercial applications., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The dry root tuber of Apios fortunei contained about 75% starch, indicating that it is an important starch resource. Starch displayed spherical, polygonal, and ellipsoidal granules with central hila. Granule sizes ranged from 3 to 30 μm with a 9.6 μm volume-weighted mean diameter. The starch had 35% apparent amylose content and exhibited C A -type crystalline structure with 25.9% relative crystallinity. The short-range ordered degree in the granule external region was approximately 0.65, and the lamellar thickness was approximately 9.6 nm. The swelling power and water solubility began to increase from 70 °C and reached 28.7 g / g and 10.8% at 95 °C. Starch had typical bimodal thermal curve in water with gelatinization temperatures from 61.8 to 83.9 °C. The 7% ( w / w ) starch-water slurry had peak, hot, breakdown, final, and setback viscosities of 1689, 1420, 269, 2103, and 683 mPa s, respectively. Rapidly digestible starch, slowly digestible starch, and resistant starch were 6.04%, 10.96%, and 83.00% in native starch; 83.16%, 15.23%, and 1.61% in gelatinized starch; and 78.13%, 17.88%, and 3.99% in retrograded starch, respectively. The above physicochemical properties of A. fortunei starch were compared with those of maize A-type starch, potato B-type starch, and pea C-type starch. The hierarchical cluster analysis based on starch structural and functional property parameters showed that A. fortunei and pea starches had similar physicochemical properties and were more related to maize starch than potato starch.

Different-colored sweet potatoes have different contents of pigments and phenolic compounds in their root tubers, which influence the isolation of starch. It is important to justify the identification of the most suitable isolation medium of starch from different colored root tubers. In this study, starches were isolated from root tubers of purple, yellow and white sweet potatoes using four different extraction media, including H₂O, 0.5% Na₂S₂O₅, 0.2% NaOH, and both 0.5% Na₂S₂O₅ and 0.2% NaOH. Their structural and functional properties were investigated and compared among different extraction media. The results showed that the granule size, apparent amylose content, lamellar peak intensity, thermal properties, and pasting properties were different among different-colored sweet potatoes due to their different genotype backgrounds. The four extraction media had no significant effects on starch structural properties, including apparent amylose content, crystalline structure, ordered degree, and lamellar peak intensity, except that the NaOH and Na₂S₂O₅ treatment were able to increase the whiteness of purple and yellow sweet potato starches. The different extraction media had some effects on starch functional properties, including thermal properties, swelling power, water solubility, and pasting properties. The above results indicated that the H₂O was the most suitable extraction medium to simply and fast isolate starch from root tubers of different-colored sweet potatoes.

The present study aimed to investigate the influence of microwave irradiation on the physical and functional properties of starch extracted from Nelumbo nucifera seed flour. The seed flour was obtained by manual grinding of seeds and irradiated at different microwave treatment time, i.e., 1, 2, 3, 4 and 5min at the low-medium intensity. The starch was extracted in distilled water and dried at room temperature using a vacuum desiccator. The morphology, crystal structure, and surface parameters of starch granules were analyzed using scanning electron microscopy, X-ray diffraction, Fourier transform infra-red spectroscopy and Brunauer, Emmett and Teller surface analysis techniques. The functional properties of starch were also determined in terms of water and oil holding capacity, swelling capacity, emulsifying activity and gelling ability. Evidently, crystallinity, surface area and pore volume of starch granules were found to be increased, while particle size and average pore size were decreased as a function of microwave treatment time. The microwave-induced variations in physical parameters significantly affected the functional properties of starch. A significant (p>0.05) exponential decrease in extraction yield and gelling ability, while an exponential increase in the functional properties of starch with increase in the microwave treatment time (R 2 =0.915-0.985) was recorded., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Native acorn starch had high purity and the granules were mainly elliptical and spherical with the mean diameter of 7.32 μm. Hydrothermal modifications slightly changed the morphology. The solubility, swelling properties and amylose leaching of acorn starch were mostly influenced by Heat-moisture treatment (HMT). XRD pattern of native starch (C-type) did not change on hydrothermal modifications, but native and annealing (ANN) modified starches showed the most crystallinity. DSC results showed that the gelatinization temperatures and enthalpy of native starch were 59.9, 71.3, and 80.6 °C and -14.9 mJ/mg, respectively, and hydrothermal treatments generally increased the gelatinization temperatures. Regarding to RVA results, peak, breakdown, trough, setback, and final viscosities of native starch were 415, 143, 272, 168, and 440 RVU, respectively, and viscosity parameters of native starch were mainly more than those of hydrothermally modified starches. Generally, the intensity of the effects of hydrothermal modifications followed the order: HMT > dual modifications > ANN., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Jackfruit is now receiving extensive attention as a new source of starch. However, jackfruit seeds are discarded as waste, although they are rich in starch. The functional properties of the starches were investigated from new Chinese jackfruit species. All the starches have a high amylose (26.56-38.34%) with a potential to become functional foods rich in resistant starch. The jackfruit starches varied from trigonal and tetragonal, round to semi-oval/bell shapes and showed significant variations in particle sizes (5.53-14.46μm). These variations led to significant differences in their functional properties, and significant correlations were found in their pasting, thermal, crystal and texture parameters. Hierarchical cluster analysis sorted the samples into three groups of 1) Malaysia 8 (M8) and ZhenZhu (ZZ); 2) Malaysia 2, Malaysia 3 and Malaysia 4, (M2, M3, M4); and 3) Xiangyinsuo 11, Xiangyinsuo 4, Xiangyinsuo 3 and Xiangyinsuo 2 (X11, X4, X3, X2). The first group could be used as food thickening or gelling agents. The second group could be applied in glutinous foods. The third group make them suitable for fillings in confectionery or weaning foods., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Optimization of the preparation of hydroxypropylated, phosphorylated and hydroxypropyl-phosphorylated glutinous rice starch was performed using a response surface methodology comprising three variables at three levels. Multi-linear regression was used to fit the degree of substitution and molar substitution against. Optimal reaction conditions were 9h, 42°C, 10% (hydroxypropylated), 148min, 150°C, 7% (phosphorylated) and 95min, 140°C, 7.8% (hydroxypropyl-phosphorylated). For hydroxypropylated, predicted optimal and experimental molar substitution values were found to be identical: 0.20. Both the phosphorylated and hydroxypropyl-phosphorylated, the predicted optimal and experimental degree of substitution values was 0.02. Static rheological analysis revealed a pseudoplastic nature for native and modified starches and an increase in apparent viscosity following modification. Dynamic rheological analysis indicated an entanglement network system for native glutinous rice starch suspension, but weak elastic gel-like structure for modified starches as the storage modulus (G') exceeded the loss modulus (G"). Additionally, chemical modification improved the freeze-thaw stability, swelling power, solubility and paste clarity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To investigate the characteristics of chemically modified wheat starch, such as oxidized (OWS), cross-linked (CLWS) and dual-modified wheat starches, cross-linked oxidized (COWS) and oxidized cross-linked (OCWS) wheat starches were obtained by 12% hydrogen peroxide (H 2 O 2 ) and 2% sodium phytate treatments, respectively. After modifications of wheat starch by cross-linking and oxidization, it was determined that native wheat starch was effectively modified with respect to the structure and physicochemical characteristics, as detected by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), Rapid Visco Analyzer (RVA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). DSC analysis demonstrated that peak temperature (T p ) 64.41°C of the COWS was the highest. The RVA viscosity indexes of CLWS were noticeably increased compared with the other four starches, of which three oxidized starch samples showed lower RVA profiles because of oxidation. The XRD result indicated that cross-linked phosphates from sodium phytate were primarily located in the amorphous regions of starch granules. After modifications by different treatments, the starch samples exhibited different morphological characteristics, including A-type and B-type wheat starch granules, which showed much closer contact with each other by the cross-linking reaction under SEM observations. The functional characteristics, including solubility, swelling power, light transmittance and freeze-thaw stability (FTS), of all five treated and untreated wheat starches demonstrated that COWS had the highest solubility at 0.57 and that CLWS showed the best swelling power at 12.63 (g/g). The paste clarity of COWS was improved to 47.72% higher than that of native starch (7.54%), and the water loss of COWS (21.62%) was the lowest, which is beneficial to the production of quick-frozen food. Our results showed that dual-modified starch by using sodium phytate and hydrogen peroxide had significantly altered structural and functional properties. The present study provides fundamental information of dual-modified wheat starch for its potential industrial application., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The present work deals with aimed to study the effect of cold plasma treatment on the functional and rheological properties of rice starch using two different power levels (40 and 60W). The changes in amylose content, turbidity, pH, water and fat absorption due to plasma treatment were evaluated. Where decrease in the turbidity and pH after the treatment was observed. Gel hydration properties and syneresis study revealed that there is an increase in leaching of amylose molecules after the treatment. Rapid Visco Analyzer examination showed an increase in pasting and final viscosities. From G' and G″ moduli determination we observed that there is decrease in retrogradation tendency of starch gels. XRD did not show any change in A-type pattern but decrease in the relative crystallinity was observed due to depolymerization caused by active plasma species. FTIR shows some of the additional functional groups after treatment. SEM showed formation of fissures on the surface of starch granules due to etching caused by the plasma species. Thus, plasma treatment can be one of the methods for physical modification of starch., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Pregelatinized (PG) starches are extensively used in food products which are processed at low temperature, to increase viscosity and offer a desirable texture. The functional properties of PG starch can be influenced by other constituents used in food matrices. Therefore the main purpose of this study was to investigate the effects of different levels of sucrose and glucose (0, 10, 20, 30 and 40% of dry starch weight basis) as two common sweeteners on drum dried pregelatinized maize starch. Samples were characterized by light microscopy, water absorption, syneresis, cold paste viscosity, texture and turbidity measurements. The results indicated that the amount of leached glucose chains to the aqueous phase, water absorption, viscosity and mechanical properties increased when increasing the sugar concentration while, syneresis and turbidity decreased. However, these effects were more obvious in samples containing sucrose than those with glucose., (Copyright © 2016. Published by Elsevier B.V.)

Four amylose-free waxy rice starches were found to give rise to gels with clearly different morphology after storage for seven days at 4°C. The thermal and rheological properties of these gels were also different. This was remarkable in light of the subtle differences in the molecular structure of the amylopectin in the samples. Addition of iodine to the amylopectin samples suggested that not only external chains, but also the internal chains of amylopectin, could form helical inclusion complexes. It is suggested that these internal helical segments participate in the retrogradation of amylopectin, thereby stabilising the gels through double helical structures with external chains of adjacent molecules. Albeit few in number, such interactions appear to have important influences on starch functional properties., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The effects of different concentrations of sodium hypochlorite (active chlorine content at 0.1, 0.2, 1.0, 2.0, 3.0, and 4.0 g/100 g) on the properties of potato starch (PS) were investigated by determining the morphological, physicochemical, crystallinity, pasting, gel texture and digestive properties. The starch granules of PS oxidized with high oxidant concentrations caused cracks and pores, and oxidation mainly acts on the amorphous regions of the starch granules. As the sodium hypochlorite concentration increases, the carbonyl content, carboxyl content, solubility, and pasting temperature of PS increased, as measured using a Rapid Visco Analyser (RVA). The swelling power, breakdown, setback, and peak and final viscosities decreased according to the RVA (P<0.05). The gel strength increased under low-intensity oxidative treatments and decreased under high-intensity oxidative treatments. Oxidative treatment decreased the digestibility of gelatinized potato starch. The slowly digestible starch and resistant starch contents increased significantly, while the rapidly digestible starch content decreased after the oxidation modification (P<0.05). Overall, PS oxidation with sodium hypochlorite improved the functional characteristics of starch and decreased starch digestibility., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Pulsed electric fields (PEF)-assisted acetylation of potato starch with different degree of substitution (DS) was prepared and effects of PEF strength, reaction time, starch concentration on DS were studied by response surface methodology. Results showed DS was increased from 0.054 (reaction time of 15 min) to 0.130 (reaction time of 60 min) as PEF strength increased from 3 to 5 kV/cm. External morphology revealed that acetylated starch with higher DS was aggravated more bulges and asperities. Fourier-transformed infrared spectroscopy confirmed the introduction of acetyl group through a band at 1730 cm(-1). The optimum sample (DS =0 .13) had lower retrogradation (39.1%), breakdown (155 BU) and setback value (149BU), while pasting temperature (62.2 °C) was slightly higher than non-PEF-assisted samples. These results demonstrated PEF treatment can be a potential and beneficial method for acetylation and achieve higher DS with shorter reaction time., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Lotus rhizome C-type starch was separated into different size fractions. Starch morphologies changed from irregular to elongated, ellipsoid, oval, and spherical with decreasing granule size. The small- and very-small-sized fractions had a centric hilum, and the other size fractions had an eccentric hilum. The different size fractions all showed C-type crystallinity, pseudoplasticity and shear-thinning rheological properties. The range of amylose content was 25.6 to 26.6%, that of relative crystallinity was 23.9 to 25.8%, that of swelling power was 29.0 to 31.4 g/g, and that of gelatinization enthalpy was 12.4 to 14.2J/g. The very-small-sized fraction had a significantly lower short-range ordered degree and flow behavior index and higher scattering peak intensity, water solubility, gelatinization peak temperature, gelatinization conclusion temperature, consistency coefficient, hydrolysis degrees, and digestion rate than the large-sized fraction. Granule size significantly positively influenced short-range ordered structure and swelling power and negatively influenced scattering peak intensity, water solubility, hydrolysis and digestion of starch (p<0.01)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Bracken (Pteridium aquilinum) is an important wild plant starch resource worldwide. In this work, starch was separated from bracken rhizome, and the physicochemical properties of this starch were systematically investigated and compared with 2 other common starches, that is, starches from waxy maize and potato. There were significant differences in shape, birefringence patterns, size distribution, and amylose content between bracken and the 2 other starches. X-ray diffraction analysis revealed that bracken starch exhibited a typical C-type crystalline structure. Bracken starch presented, respectively, lower and higher relative degree of crystallinity than waxy maize and potato starches. Ordered structures in particle surface differed among these 3 starches. The swelling power tendency of bracken starch in different temperature intervals was very similar to that of potato starch. The viscosity parameters during gelatinization were the lowest in waxy maize, followed by bracken and potato starches. The contents of 3 nutritional components, that is, rapidly digestible, slowly digestible, and resistant starches in native, gelatinized, and retrograded starch from bracken rhizome presented more similarities with potato starch than waxy maize starch. These finding indicated that physicochemical properties of bracken starch showed more similarities with potato starch than waxy maize starch., (© 2015 Institute of Food Technologists®)